Submission #556337

#	Time	Username	Problem	Language	Result	Execution time	Memory
556337		ngpin04	Evacuation plan (IZhO18_plan)	C++14	100 / 100	1010 ms	32748 KiB

plan

#include <bits/stdc++.h>
#define fi first
#define se second
#define mp make_pair
#define TASK ""
#define ALL(x) (x).begin(), (x).end() 
using namespace std;
template <typename T1, typename T2> bool mini(T1 &a, T2 b) {
	if (a > b) {a = b; return true;} return false;
}
template <typename T1, typename T2> bool maxi(T1 &a, T2 b) {
	if (a < b) {a = b; return true;} return false;
}
const int N = 1e5 + 5; 
const int oo = 1e9;
const long long ooo = 1e18;
const int mod = 1e9 + 7; // 998244353;
const long double pi = acos(-1);

vector <pair <int, int>> adj[N];
vector <int> qr[N];

int par[N];
int lo[N];
int hi[N];
int s[N];
int t[N];
int d[N];
int n,m,k,q;

int getpar(int u) {
	return (par[u] < 0) ? u : (par[u] = getpar(par[u]));
}

void join(int u, int v) {
	u = getpar(u);
	v = getpar(v);
	if (u == v)
		return;
	if (par[u] > par[v])
		swap(u, v);
	par[u] += par[v];
	par[v] = u;
}

int main() {
	ios_base::sync_with_stdio(0);
	cin.tie(0);
	#ifdef ONLINE_JUDGE
	// freopen(TASK".inp","r",stdin);
	// freopen(TASK".out","w",stdout);
	#endif
	cin >> n >> m;
	for (int i = 1; i <= m; i++) {
		int u,v,w;
		cin >> u >> v >> w;
		adj[u].push_back(mp(v, w));
		adj[v].push_back(mp(u, w));
	}
	cin >> k;
	for (int i = 1; i <= n; i++)
		d[i] = oo;

	priority_queue <pair <int, int>> heap;
	for (int i = 1; i <= k; i++) {
		int v; cin >> v;
		d[v] = 0;
		heap.push(mp(0, v));
	}

	while (heap.size()) {
		int u = heap.top().se;
		int cur = -heap.top().fi;
		heap.pop();
		if (cur != d[u])
			continue;
		for (pair <int, int> to : adj[u]) {
			int v = to.fi;
			int w = to.se;
			if (mini(d[v], d[u] + w))
				heap.push(mp(-d[v], v));
		}
	}

	vector <int> node(n, 0);
	iota(ALL(node), 1);
	sort(ALL(node), [](int i, int j) {
		return d[i] < d[j];
	});

	cin >> q;
	for (int i = 1; i <= q; i++) {
		cin >> s[i] >> t[i];
		lo[i] = 0;
		hi[i] = n;
	}

	for (int rep = 0; rep < 20; rep++) {
		for (int i = 0; i < n; i++)
			qr[i].clear();

		for (int i = 1; i <= q; i++) {
			int mid = (lo[i] + hi[i]) >> 1;
			qr[mid].push_back(i);
		}

		memset(par, 0, sizeof(par));
		for (int i = n - 1; i >= 0; i--) {
			int u = node[i];
			par[u] = -1;
			for (pair <int, int> to : adj[u]) {
				int v = to.fi;
				if (par[v] != 0)
					join(u, v);
			}

			for (int j : qr[i]) {
				int u = s[j];
				int v = t[j];
				if (par[u] != 0 && par[v] != 0 && getpar(u) == getpar(v))
					lo[j] = i;
				else
					hi[j] = i;
			}
		}
	}

	for (int i = 1; i <= q; i++)
		cout << d[node[lo[i]]] << "\n";
	return 0;
}

• Subtask 1: 10 / 10
• Subtask 2: 13 / 13
• Subtask 3: 12 / 12
• Subtask 4: 19 / 19
• Subtask 5: 46 / 46